JP2006332036A - Method for manufacturing display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid device deterioration and degradation in performance, which are caused by existence of insulating layer absolutely necessary for a conventional process of applying a luminescent polymer selectively. <P>SOLUTION: A method for manufacturing organic electro luminescence device applies a composition containing an organic electroluminescence compound onto a plurality of electrodes to form organic electroluminescence layers on the respective electrodes. A substrate, of which water repellent treatment is given to portions between electrodes and/or surfaces of the electrodes, is used, and the composition is applied onto the substrate. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an organic electroluminescence display device, an organic electroluminescence display device manufactured by the method, and an electronic apparatus using the same. More specifically, in a method for producing a display device comprising a plurality of corresponding organic electroluminescence elements by forming an organic electroluminescence layer on the plurality of electrodes, a water repellent treatment is performed between the electrodes and / or the surface of the electrodes. The present invention relates to a method for producing an organic electroluminescence display device using a substrate to which an organic electroluminescence layer (light emitting layer) is formed, an organic electroluminescence display device produced by this method, and an electronic apparatus using the same.

  In recent years, organic electroluminescence devices have attracted attention as display devices that will realize the ultimate thinness, light weight, small size, and low power consumption in the future. This organic electroluminescence device is expected to be widely used in the future. In particular, when combined with a low-temperature polycrystalline silicon thin film transistor, further reduction in thickness, weight and size can be realized. Low temperature polycrystalline silicon thin film transistor driven organic electroluminescence device can be one of ideal devices (T. Shimoda, M. Kimura, et al., Proc. AsiaDisplay 98, 217 (1998), M. Kimura, et al. , IEEE Trans. Elec. Dev., To bepublished;

  As a manufacturing method of an organic electroluminescence element, there are a vacuum process and a liquid phase process. In general, a vacuum process such as a vapor deposition method or a sputtering method is used for a low molecular weight organic electroluminescence element (in this specification, each pixel constituting a display panel is referred to as an organic electroluminescence element).

On the other hand, letterpress printing, intaglio printing, stencil printing, or plateless printing is used for the polymer organic electroluminescence element. In the plateless printing method, a wet process such as a spin coating method, a squeegee coating method, an ink jet method, or a nozzle coating method is used.
In particular, the ink-jet method is said to be a promising method because it can simultaneously perform film formation and patterning of colors.

However, the inkjet method is a method of patterning thin films having different characteristics on the same substrate by coating, and there arises a problem that different thin film materials are mixed on the substrate and the discharged liquid material flows out to adjacent pixels. Therefore, it is necessary to provide an insulating layer having a structure for separating the elements between the pixels (Japanese Patent Laid-Open No. 2002-305077; Patent Document 1). In addition, an insulating layer here refers to the structure provided between each pixel and isolate | separating the organic electroluminescent element of each pixel.
However, the method for forming an organic electroluminescent device by forming this insulating layer has the following problems.

  As the insulating layer, a first insulating layer and a second insulating layer as described in Proc. Asia Display 98, 217 (1998), IEEE Trans. Elec. Dev. Structure is used. A cross-sectional view of such a conventional organic electroluminescence device is shown in FIG. 1, and its manufacturing method (process) is shown in FIGS.

The organic electroluminescence device of this conventional example includes a first insulating layer (1) and a second (2) insulating layer (2) on the anode (3). After these first insulating layer (1) and second insulating layer (2) are formed, an organic electroluminescent layer (4) formed of a different compound corresponding to each color is formed by an inkjet method or the like. Then, the cathode (5) is formed thereon, and the organic electroluminescence device is completed.
The second insulating layer (2) is controlled to be liquid repellent by an appropriate surface treatment. Thereby, the color mixing at the time of apply | coating an organic electroluminescent layer (4) to each pixel by an inkjet process etc. is suppressed.

However, by controlling the second insulating layer (2) to be liquid repellent, a region (6) in which the organic electroluminescent layer (4) becomes thin is generated around the edge of the second insulating layer (2). Therefore, it becomes difficult to form a uniform film.
If the anode (3) and the cathode (5) are present in the part (6), a short circuit occurs, and the leakage current increases remarkably. Therefore, the first insulating layer (1) is provided around the edge of the second insulating layer (2) so as not to cause a short circuit.

In the process shown in FIG. 2, the anode (3) is made of ITO, and the first insulating layer (1) is plasma enhanced chemical vapor deposition (PECVD) of ethyl silicate (TEOS). by being formed of SiO _2, the second insulating layer (2) is formed by spin coating the polyimide.

  In this conventional example, the first insulating layer (1) is formed on the anode (3) made of ITO (FIG. 2 (a)), and then the portion on the anode (3) where light emission is desired. Then, patterning is performed so that the opening comes to (FIG. 2B). Next, a second insulating layer (2) is formed by a liquid phase process (FIG. 2 (c)), and is patterned so that an opening is formed in a portion on the anode (3) where light emission is desired (FIG. 2). 2 (d)).

As can be seen from FIG. 2, a fairly thick thin film is used for the first insulating film (1), so that the second insulating layer (2) has an opening at the opening of the first insulating layer (1). The thickness is significantly thicker than the other parts.
For this reason, when etching the second insulating layer (2), if an etching time is set in accordance with the thin portion, an etching residue may be generated in the thick portion. (7) in FIG. 2 (d) is an etching residue of the opening generated in this way. Further, if the etching time is set in accordance with the thick part, a large side etch may occur in the thin part.

  Further, since the first insulating layer (1) is formed by a vacuum process, the surface of the first insulating layer (1) is not flat. That is, undulations exist on the surface depending on the presence or absence of the anode (3). Corresponding to the undulations on the surface, there is a non-uniformity of the film thickness of the second insulating layer (2). Due to this non-uniform film thickness, the etching of the second insulating layer (2) is performed. Residues may be generated. (8) in FIG. 2 (d) is an etching residue of the surface undulation generated in this way. If the etching residue (8) on the surface undulations is to be completely removed, the performance degradation of the organic electroluminescence device caused by the residue and surface irregularities, such as the possibility of large side etching occurring elsewhere, It is a big problem.

  In addition, in order to improve the light emission characteristics of the organic electroluminescence (EL) element, it is necessary to control the work function and the like to the optimum values according to the compound in addition to the cleanliness and unevenness of the surface on which the organic electroluminescence compound is formed. (JP 2004-63210 A; Patent Document 2). Therefore, it is necessary to perform a process such as liquid cleaning of the surface on which the organic electroluminescent compound is to be applied, or removing impurities such as organic substances adhering to the substrate surface by oxygen plasma treatment, etc. It is very difficult to completely clean the surface of the substrate on which the layer exists or to perform surface treatment uniformly (Japanese Patent Laid-Open No. 2001-126867; Patent Document 3).

  In spite of the disadvantages as described above, the organic electroluminescence device must still be prepared by providing an insulating layer in the structure of the conventional organic electroluminescence device using the polymer organic electroluminescence compound. The basic structure is a laminated structure of anode / hole injection layer / organic electroluminescence layer / cathode, and an organic electroluminescence device that can withstand practical use unless a hole injection layer is provided between the anode and the organic electroluminescence layer. This is because it could not be created (Japanese Patent Publication No. 2000-516760; Patent Document 4).

As the hole injection layer, any compound can be used as long as it has a function of efficiently injecting holes from the anode into the organic electroluminescence layer. Conventionally, a water-soluble conductive polymer (from Starck Vitec) Baitron (registered trademark) is widely used. A necessary condition for the hole injection layer is that the hole injection layer is not redissolved by the organic electroluminescence compound applied and laminated thereon.
In addition, since the organic electroluminescent compound is dissolved and applied in an organic solvent, the hole injection layer is preferably insoluble (that is, water-soluble) in the organic solvent.

In other words, as a step of creating an organic electroluminescence device using an organic electroluminescence compound that requires a hole injection layer, it is necessary to first apply a water-soluble hole injection layer to the anode surface. However, when water repellency is reached, the hole injection layer is repelled and cannot be applied.
Therefore, it is necessary to perform patterning so that the surface portion of the electrode where the hole injection layer is to be formed is kept hydrophilic, and a so-called embankment-like water-repellent insulating layer is formed at the portion between the electrodes which is not desired to be formed. Therefore, the formation of the insulating layer was essential.

JP 2002-305077 A JP 2004-63210 A JP 2001-126867 A Patent Publication 2000-516760 T. Shimoda, M. Kimura, et al., Proc. AsiaDisplay 98, 217 (1998), M. Kimura, et al., IEEE Trans. Elec. Dev., To bepublished Proc. Asia Display 98, 217 (1998), IEEE Trans. Elec. Dev.

  Therefore, an object of the present invention is to provide a stable and high state even when an insulating layer that impairs the cleanliness and smoothness of the element surface necessary for improving the characteristics of the organic electroluminescence device is not formed, or even when the insulating layer is much thinner. An object of the present invention is to provide a method capable of producing a high performance organic electroluminescence device.

As a result of intensive research to solve the above problems, the present inventors have not formed an insulating layer that has been conventionally required for coating film formation of a polymer organic electroluminescent light emitting compound, or the insulating layer is not much. The present inventors have found a method for producing an organic electroluminescent device that can be applied with an electroluminescent light-emitting compound in a very thin state, and that can avoid degradation of the performance of the device derived from an insulating layer.
That is, by providing water repellency by forming a water-repellent thin film on the surface of the substrate that is the application surface of the layer containing the organic electroluminescent compound, the insulating layer is not formed, or the insulating layer is far An organic electroluminescent compound layer can be formed by patterning even in a thin state, and a method for manufacturing an organic electroluminescent device with good organic electroluminescent characteristics has been found, and the present invention has been completed.

The present invention has the following configuration.
1. In a method for manufacturing an organic electroluminescent device in which an organic electroluminescent layer is formed on each electrode by applying a composition containing an organic electroluminescent compound on a plurality of electrodes, water repellent treatment is performed between the electrodes and / or on the surface of the electrodes. The manufacturing method of the organic electroluminescent apparatus characterized by using the board | substrate which gave this, and apply | coating the said composition.
2. 2. The method for producing an organic electroluminescence device according to 1, wherein the water repellent treatment includes formation of a water repellent thin film.
3. 3. The method for producing an organic electroluminescent device according to 2 above, wherein the water-repellent thin film has a thickness of 0.2 to 30 nm.
4). 3. The organic electroluminescence device according to 2 above, wherein an insulating layer having a thickness of 0 to 3000 nm from the substrate surface and an angle of 0 to 80 degrees viewed from the upper surface of the electrode is provided around the plurality of electrodes formed with the water repellent layer. Manufacturing method.
5. 5. The organic electroluminescence device according to 4 above, wherein an insulating layer having a thickness of 0 to 500 nm from the substrate surface and an angle of 0 to 30 degrees viewed from the upper surface of the electrode is provided around the plurality of electrodes formed with the water repellent layer. Manufacturing method.
6). 3. The method for producing an organic electroluminescence device according to 1 or 2 above, wherein the organic electroluminescence layer is a layer containing a polymer organic electroluminescence compound.
7). 3. The method for producing an organic electroluminescence device according to 2 above, wherein the method for forming the water-repellent thin film is a treatment for forming a fluoride film on the surface of the substrate.
8). 8. The method for producing an organic electroluminescence device according to 7 above, wherein the fluoride film is formed by plasma treatment using a fluorocarbon-based compound as a reaction gas.
9. 3. The method for producing an organic electroluminescent device according to 2 above, wherein the surface roughness of the water-repellent thin film is 1 nm or less in terms of Ra value.
10. 3. The method for producing an organic electroluminescent device according to 2 above, wherein the surface protrusion height of the water repellent thin film is 10 nm or less.
11. 3. The method for producing an organic electroluminescence device according to 2 above, wherein the water-repellent thin film is formed as an organic thin film by a radio frequency (RF) plasma treatment method of a gaseous organic compound.
12 3. The method of manufacturing an organic electroluminescence device according to 2 above, wherein the anode (surface) is subjected to high-frequency plasma treatment, and then a thin film is formed and then optimized to form a water-repellent thin film.
13. 3. The method according to 2 above, wherein the anode (surface) is subjected to high-frequency plasma treatment, a thin film is formed by a high-frequency (RF) plasma treatment method of a gaseous compound, and then optimized to form a water-repellent thin film. Manufacturing method of the organic electroluminescence device.
14 _3. The method for producing an organic electroluminescence device according to 2 above, wherein the method of forming the water-repellent thin film is a method of forming a SiO ₂ thin film by treating the substrate surface by a sputtering method.
15. 14. The method for producing an organic light-emitting element according to 12 or 13, wherein the optimization process is a cleaning process using a solvent.
16. 14. The production of an organic light-emitting device according to 12 or 13 above, wherein high-frequency plasma treatment is performed in a gas containing one or more selected from oxygen, argon, and fluorocarbon in order to adjust the surface roughness of the anode and the height of the protrusions. Method.
17. 3. The method for producing an organic electroluminescence device according to 2 above, wherein the water contact angle with the water-repellent thin film is 30 ° or more.
18. 3. The method for producing an organic electroluminescent device according to 1 or 2 above, wherein a composition containing an organic electroluminescent compound is applied onto a plurality of electrodes by letterpress printing, intaglio printing, stencil printing or plateless printing.
19. 19. The method for producing an organic electroluminescence device according to 18 above, wherein the composition containing the organic electroluminescence compound is applied by a plateless printing method by ink jetting.
20. 19. The method for producing an organic electroluminescent device according to 18 above, wherein the composition containing the organic electroluminescent compound is applied by a nozzle coating method.
21. 3. The method for producing an organic electroluminescent device according to 1 or 2, wherein the organic electroluminescent compound is a phosphorescent polymer compound.
22. 3. The method for producing an organic electroluminescent device according to 1 or 2 above, wherein the organic electroluminescent compound is a fluorescent light-emitting polymer compound or a non-conjugated phosphorescent polymer.
23. 23. An organic electroluminescence device manufactured by the manufacturing method according to any one of 1 to 22.
24. 23. A substrate for an organic electroluminescence device manufactured by a method included in the manufacturing method according to any one of 1 to 22.
25. 24. An electronic apparatus comprising the organic electroluminescence device as described in 23 above.
26. 26. The electronic device as described in 25 above, wherein the electronic device is a surface emitting light source, a device backlight, a device, a lighting device, an interior, or an exterior.

  According to the manufacturing method of the present invention, it is possible to apply the organic electroluminescent light emitting compound even when the insulating layer is not formed on the surface of the anode substrate or when the insulating layer is much thinner. An electroluminescent device can be manufactured.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings (FIGS. 3 to 20).
The method for producing an organic electroluminescence device according to the present invention comprises forming a water repellent thin film on the surface of an organic electroluminescent light emitting compound in a predetermined pattern shape, preferably a nozzle coat. In this method, an organic electroluminescence device is manufactured by coating a film by a method.

[Configuration of organic electroluminescence device]
First, the configuration of the organic electroluminescence device will be described. First, a film (3) made of an anode material is formed on the surface of a flat substrate (S in FIG. 8). Here, examples of the substrate include a glass substrate, but are not limited thereto, and any insulating substrate that is transparent with respect to the emission wavelength of the light emitting material can be used. Alternatively, a substrate with a TFT (thin film transistor) may be used. Also, known flexible materials such as transparent plastics such as PET (polyethylene terephthalate) and polycarbonate can be used.

[About anode]
The anode formed on the substrate is most commonly a conductive and light-transmitting layer typified by ITO (indium tin oxide). When observing organic light emission through a substrate, the light transmission between the anode and the substrate is essential, but in applications where organic light emission is observed through top emission, that is, through the upper electrode, the transparency of the anode is not necessary, and the work function is Any suitable material such as a metal or metal compound higher than 4.1 eV can be used as the anode.

  For example, gold, nickel, manganese, iridium, molybdenum, palladium, platinum, or the like can be used in combination or singly. The anode can also be selected from the group consisting of metal oxides, nitrides, selenides and sulfides. Moreover, what formed the said metal into a film as a thin film of 1-3 nm so that light transmittance may not be impaired on the surface of ITO with favorable light transmittance can also be used as an anode. As a film formation method on the surface of these anode materials, an electron beam evaporation method, a sputtering method, a chemical reaction method, a coating method, a vacuum evaporation method, or the like can be used. The thickness of the anode is preferably 2 to 300 nm.

[Water repellent layer]
In the present invention, a substrate having a water repellent treatment between electrodes and / or the surface of the electrodes is used. By applying the water repellent treatment between the electrodes, the levee-like insulating layer becomes unnecessary, and by applying the water repellent treatment to the electrode surface, the hole injection layer becomes unnecessary. A method of using any of the water repellent treated substrates is also included in the present invention, but preferably the water repellent treatment is performed between the electrodes and the electrode surface.

The water repellent treatment will be described more specifically by taking as an example a configuration using ITO as the anode.
The ITO film formed on the substrate is patterned on an electrode having a predetermined shape by using a photolithography technique. In this way, a plurality of ITO electrodes having a shape to be coated with the organic electroluminescent compounds of the respective colors are formed on the surface of the substrate.

  Next, a surface treatment for imparting water repellency is performed on the substrate on which ITO is formed. Typically, a water-repellent thin film (hereinafter sometimes referred to as a water-repellent layer) is formed. A method of forming a water-repellent thin film includes a wet process method in which it is applied after dissolving in a solvent, a high-frequency plasma treatment, a sputtering treatment, a corona treatment, a UV ozone irradiation treatment, a vacuum deposition, a laser transfer method, or an oxygen plasma treatment method. These methods can be roughly classified into dry process methods such as the above, and both of them can use commonly used film forming methods alone or in combination.

  The thickness of the formed water-repellent thin film is preferably 0.2 to 30 nm, and more preferably 0.2 to 10 nm. The composition and chemical structure of the organic substance that forms the thin film are not particularly limited, but the properties after the thin film formation have an appropriate water repellency that gives an appropriate film thickness and coating shape to the light emitting compound laminated on the upper layer. Required. Furthermore, it does not re-dissolve by applying a luminescent compound laminated on the upper layer, does not scatter or diffuse due to physical impact during the coating process, has good adhesion to the luminescent compound, and has an appropriate ionization potential. Can be mentioned. Any compound can be used as long as it is a compound that imparts these properties to the anode substrate.

As an example of a compound having good adhesion to the luminescent compound, a compound having a partial structure having a strong interaction with the luminescent compound is desirable. As the partial structure, for example, it is desirable to appropriately include an aromatic ring, an alkyl chain, fluorine or the like that can be expected to have a hydrophobic interaction. Moreover, it does not necessarily need to be an organic substance, and inorganic substances, such as a metal fluoride and a metal oxide, may be sufficient. A method of forming a thin film by sputtering a compound containing silicon such as SiO ₂ on the metal surface is also effective.
The appropriate ionization potential on the surface of the water-repellent thin film is preferably 4.5 to 6.0 eV, more preferably 4.8 to 5.5 eV, although it depends on the type of organic electroluminescent compound used.

  When manufacturing a water-repellent thin film by applying wet process, spin coating method, casting method, micro gravure coating method, gravure coating method, bar coating method, roll coating method, wire bar coating method, dip coating method Then, after forming a film by using a coating method such as a spray coating method, a screen printing method, a flexographic printing method, an offset printing method, or an inkjet printing method, an optimization process is performed. That is, it can be obtained by washing the surface with a solvent capable of dissolving the luminescent compound component in order to improve or change the film properties. In the cleaning step using a solvent, a spin coating method, an ink jet method, a dip method, or the like can be used as in the step of applying a water-repellent thin film. In other words, by washing the surface with a solvent, it is possible to remove scattering and diffusing components generated in the process of newly laminating a luminescent compound on the upper layer, and to completely remove irregularities and protrusions present on the substrate surface. By adjusting the number of times the surface is washed with a solvent after it has been fully coated, it is possible not only to remove excess free components adhering to the surface, but also to realize a water-repellent thin film that maintains surface smoothness. Is possible. It is also possible to adjust the surface energy by treating the surface with a solvent. Since the contact angle with respect to water changes from 5 to 140 ° by adding a new cleaning process on the basis of immediately after film formation, it is possible to adjust the surface energy depending on the polarity of the luminescent compound to be laminated. In addition, the same effect can be obtained by subjecting the thin film to annealing treatment in various atmospheres, or radiation treatment such as ion implantation, UV irradiation, UV ozone irradiation, or additional oxygen, nitrogen or hydrogen plasma treatment. Obtainable.

  The compound that can be used in the film formation by the wet process is not particularly limited as long as it is a compound having good adhesion to the luminescent compound contained in the anode surface and its upper layer, but the anode buffer that has been generally used so far Is more preferable. Examples thereof include conductive polymers such as PEDOT, which is a mixture of poly (3,4) -ethylenedioxythiophene and polystyrene sulfonate, and PANI, which is a mixture of polyaniline and polystyrene sulfonate. Further, an organic solvent such as toluene or isopropyl alcohol may be added to these conductive polymers. Moreover, the conductive polymer containing 3rd components, such as surfactant, may be sufficient. The surfactant is, for example, selected from the group consisting of alkyl groups, alkylaryl groups, fluoroalkyl groups, alkylsiloxane groups, sulfates, sulfonates, carboxylates, amides, betaine structures, and quaternized ammonium groups. Surfactants containing one kind of group are used, but fluoride-based nonionic surfactants can also be used.

The water-repellent thin film can also be formed by a dry process such as radio frequency (RF) plasma treatment. In particular, high-frequency plasma treatment in which organic gas is deposited as a solid on a solid layer by applying glow discharge to the organic gas can provide a film having excellent adhesion and high durability. For example, a thin film made of fluorocarbon can be formed on a substrate by glow discharge of gaseous fluorocarbon in RF plasma and bringing the substrate into contact with the substrate. The fluorocarbon thin film can be formed by plasma-treating gaseous fluorocarbon in an RF apparatus cabinet, but gaseous fluorocarbons are CF ₄ , C ₃ F ₈ , C ₄ F ₁₀ , CHF ₃ , C ₂ F ₄ and C. it can be selected from the group consisting of ₄ F _8.

  Plasma is generated by applying (outputting) a radio frequency (RF) voltage at an appropriate power level in the apparatus cabinet. Although the reaction temperature varies depending on parameters such as output, gas flow rate, and processing time, it is preferable to adjust the film thickness appropriately with good reproducibility by providing a temperature adjustment function in the apparatus cabinet. The contact angle of the surface of the anode substrate on which the thin film thus obtained, in particular, the thin film containing fluoride is formed, can be controlled from 30 ° to 170 °. In order to satisfactorily apply the organic electroluminescence compound subsequently, 40 ° to 150 ° is preferable, and 60 ° to 120 ° is more preferable. In this way, an anode substrate that is ready to receive the application of the organic electroluminescent compound of each color is manufactured.

  In addition, when forming a water-repellent thin film by a dry process using high-frequency plasma treatment, the anode surface can be etched by controlling the plasma generation conditions. That is, it is possible to simultaneously perform surface smoothing utilizing the etching action of the anode surface and film formation by high-frequency plasma treatment. As described above, for example, a silicon compound may be formed into a thin film by sputtering.

  The obtained thin film can be optimized in the same manner as the water-repellent thin film formed by the above-described coating method. That is, the surface can be further treated to improve or change its characteristics to make it more appropriate. Specifically, by washing with a solvent, the smoothness and film thickness of the film can be set within an appropriate range, and durability can be improved. Here, the smoothness of the film means that the surface roughness (Ra value) is 1 nm or less and the height of the surface protrusion is 10 nm or less, and the appropriate film thickness means 0.2 to 30 nm. Similarly, the surface energy can be adjusted. Furthermore, the same effect can be obtained by subjecting the thin film to annealing treatment in various atmospheres, or radiation treatment such as ion implantation, UV irradiation, UV ozone irradiation or additional oxygen, nitrogen or hydrogen plasma treatment. Can be obtained.

  If necessary, the performance of the water-repellent thin film that is overcoated by pre-treating the anode surface when forming the water-repellent thin film (adhesion with the anode substrate, finished smoothness, reduction of the hole injection barrier, etc.) ) Can also be improved. Examples of the pretreatment method include high-frequency plasma treatment, sputtering treatment, corona treatment, UV ozone irradiation treatment, and oxygen plasma treatment.

[Insulating layer]
In the present invention, it is not necessary to provide an insulating layer between electrodes (referred to as a layer other than the water repellent layer formed by the water repellent treatment), but it is possible to provide this. As described above, the insulating layer is provided between the pixels in order to separate the organic electroluminescence elements of the pixels. In the organic electroluminescence device of the present invention, in order to maintain the cleanliness of the substrate, an insulating layer much thinner than the conventional one is used. Specifically, the thickness from the substrate surface is 0 to 500 nm, and particularly preferably 0 to 200 nm. In the case of 0 nm, the insulating layer is not used.

In addition, the inclination of the insulating layer shown in FIG. 9A is preferably as gentle as possible from the anode surface toward the edge. A desirable angle in this case is 0 to 30 degrees, and 2 to 10 degrees is particularly preferable. Here, the state of 0 degree is a state in which the insulating layer is in contact with the same height as the ITO as shown in FIG. 9B and completely covers the edge of the ITO. Further, as shown in FIG. 9C, the insulating layer may be continuously filled between ITO.
Thus, in the organic electroluminescence device of the present invention, it is preferable to use an insulating layer that is much thinner than the prior art. In the prior art, the light emitting layer cannot be applied unless the height of the insulating layer is sufficient, but in the present invention, the light emitting layer can be suitably applied by forming a water-repellent thin film on the surface of the substrate.
Examples of the compound forming the insulating layer include fluorocarbon and SiO ₂ thin film.

[Step of forming organic electroluminescent compound]
The process of forming the organic electroluminescence compound layer on the anode substrate will be described. The organic electroluminescent compound used for forming the organic electroluminescent layer of the organic electroluminescent device of the present invention is described in Hiroshi Omori: Applied Physics, Vol. 70, No. 12, pages 1419–1425 (2001). Examples thereof include low molecular light emitting compounds and polymer light emitting compounds. Among these, a high molecular weight light emitting compound is preferable in terms of simplifying the device manufacturing process, and a phosphorescent light emitting compound is preferable in terms of high luminous efficiency. Therefore, a phosphorescent polymer compound is particularly preferable.

  The phosphorescent polymer compound used as the light emitting layer of the organic electroluminescence device of the present invention is not particularly limited as long as it is a polymer compound that emits phosphorescence at room temperature. Examples of specific polymer structures include conjugated polymer structures such as poly (p-phenylene) s, poly (p-phenylene vinylenes), polyfluorenes, polythiophenes, polyanilines, polypyrroles, polypyridines, etc. And a polymer structure in which a phosphorescent site (typically, a monovalent group or a divalent group of a transition metal complex or a rare earth metal complex described below can be exemplified) is bonded to the skeleton. . In these polymer structures, the phosphorescent site may be incorporated into the main chain or into the side chain.

Another example of the polymer structure of the phosphorescent polymer compound is a polymer having a non-conjugated polymer structure such as polyvinyl carbazole, polysilanes, polytriphenylamines, etc., and a phosphorescent site bonded thereto. The structure can be mentioned. In these polymer structures, the phosphorescent site may be incorporated into the main chain or into the side chain.
Another example of the polymer structure of the phosphorescent polymer compound is a dendrimer having a phosphorescent site. In this case, the phosphorescent light emitting site may be incorporated in any of the central core, branched portion, and terminal portion of the dendrimer.

In the above polymer structure, phosphorescence is emitted from a phosphorescent light emitting site bonded to a conjugated or nonconjugated skeleton, but phosphorescence may be emitted from a conjugated or nonconjugated skeleton itself.
The phosphorescent polymer compound used in the organic electroluminescence device of the present invention has a degree of freedom in material design, a relatively easy phosphorescence emission, an easy synthesis, and a solubility in a solvent. In view of the fact that the coating solution is high and the preparation of the coating solution is easy, a polymer having a non-conjugated polymer structure as a skeleton and a phosphorescent site bonded thereto (hereinafter referred to as a non-conjugated phosphorescent polymer) is preferable. .

  The non-conjugated phosphorescent polymer is composed of a phosphorescent site and a carrier transporting site. As a typical polymer structure, depending on the binding state of the phosphorescent site and the carrier transporting site, (1) When both the phosphorescent site and the carrier transporting site are in the main chain of the polymer, (2) the phosphorescent site is in the side chain of the polymer and the carrier transporting site is in the main chain of the polymer (3) when the phosphorescent moiety is in the main chain of the polymer and the carrier transporting moiety is in the side chain of the polymer, (4) both the phosphorescent moiety and the carrier transporting moiety are The case where it exists in a side chain can be illustrated.

  In addition, the above polymer structure may have a cross-linked structure, or a hole transport compound, an electron transport compound, and a light emitting compound are not bonded to each other and are independent single polymers (homopolymers) or two kinds of polymers. A polymer in which a compound is polymerized may be used. Furthermore, the polymerized compound may be one or more selected from three of a hole transport compound, an electron transport compound, and a light emitting compound, and the remaining compound may be a low molecule.

The non-conjugated phosphorescent polymer may have two or more types of phosphorescent sites (each may be in the main chain or in the side chain). Two or more types of carrier transporting sites may be present (they may be in the main chain, in the side chain, or not bonded).
The molecular weight of the non-conjugated phosphorescent polymer is preferably 1,000 to 100,000, more preferably 10,000 to 500,000 in terms of weight average molecular weight.

  As the phosphorescent site, a monovalent group or a polyvalent group of a bivalent group or more that emits phosphorescence at room temperature can be used, but a monovalent group or divalent group of a transition metal complex or a rare earth metal complex can be used. Groups are preferred. The transition metal used in the above transition metal complex includes the first transition element series of the periodic table, that is, Sc of atomic number 21 to Zn of 30 and the second transition element series, that is, Y of 48 of atomic number 39 to 48. Up to Cd, includes the third transition element series, that is, from Hf of atomic number 72 to Hg of 80. The rare earth metal used in the rare earth metal complex includes a lanthanoid series in the periodic table, that is, La from atomic number 57 to 71 Lu.

  In addition, as ligands that can be used in the above transition metal complexes and rare earth metal complexes, G. Wilkinson (Ed.), Comprehensive Coordination Chemistry (Plenum Press, 1987), Akio Yamamoto “Organic Metal Chemistry: Fundamentals and Applications” (Liaohuabo, 1982) The ligand etc. can be illustrated. Among them, halogen ligands, nitrogen-containing heterocyclic ligands (phenylpyridine ligands, benzoquinoline ligands, quinolinol ligands, bipyridyl ligands, terpyridine ligands, phenanthroline ligands Ligands, etc.), diketone ligands (acetylacetone ligand, dipivaloylmethane ligand, etc.), carboxylic acid ligands (acetic acid ligand, etc.), phosphorus ligands (triphenylphosphine coordination) And a carbon monoxide ligand, an isonitrile ligand, and a cyano ligand. The metal complex may contain a plurality of ligands in one complex. Moreover, a binuclear complex or a polynuclear complex can also be used as a metal complex.

As the carrier transporting site, a hole transporting property, an electron transporting property, or a bipolar monovalent group that transports both holes and electrons, or a polyvalent group having two or more divalent groups can be used. As a hole transporting carrier transporting site, carbazole, triphenylamine, N, N′-diphenyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4,4′diamine (TPD) Examples of the monovalent group or the divalent group. In addition, examples of the electron transporting carrier transporting site include quinolinol derivative metal complexes such as trisaluminum quinolinol (Alq ₃ ), oxadiazole derivatives, triazole derivatives, imidazole derivatives, monovalent or divalent groups of triazine derivatives, boron Examples of such compounds are listed below. Examples of the bipolar carrier transport site include a monovalent or divalent group of 4,4′-N, N′-dicarbazole-biphenyl (CBP).

  The light emitting layer of the organic electroluminescence device of the present invention can be formed of only the above phosphorescent polymer compound or conjugated polymer. In addition, the light emitting layer can be formed as a composition in which another carrier transporting compound is mixed in order to supplement the carrier transporting property of the phosphorescent light emitting polymer compound or the conjugated polymer. That is, when the phosphorescent polymer compound is hole transporting, the electron transporting compound can be mixed, and when the phosphorescent polymer compound is electron transporting, the hole transporting compound can be mixed. it can. Here, the carrier transporting compound to be mixed with the phosphorescent polymer compound may be either a low molecular compound or a polymer compound.

  As a low molecular weight hole transporting compound that can be mixed with the phosphorescent polymer compound, N, N′-diphenyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl- 4,4′diamine (TPD), 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD), 4,4 ′, 4 ″ -tris (3-methyl Examples of known hole transporting compounds include triphenylamine derivatives such as phenylphenylamino) triphenylamine (m-MTDATA). In addition, as a polymer hole transporting compound that can be mixed with the phosphorescent polymer compound, a polymerized functional group is introduced into a polyvinylcarbazole or triphenylamine-based low-molecular compound to form a polymer. Examples thereof include, for example, a polymer compound having a triphenylamine skeleton disclosed in JP-A-8-157575.

On the other hand, examples of low molecular weight electron transporting compounds that can be mixed with the phosphorescent polymer compound include quinolinol derivative metal complexes such as trisaluminum quinolinol (Alq ₃ ), oxadiazole derivatives, triazole derivatives, and imidazole derivatives. And triazine derivatives. In addition, as a high molecular electron transporting compound that can be mixed with the phosphorescent high molecular weight compound, a polymer obtained by introducing a polymerizable functional group into the low molecular weight electron transporting compound, For example, poly PBD disclosed in JP-A-10-1665 can be exemplified.

  In addition, for the purpose of improving the physical properties and the like of the film obtained by forming the phosphorescent polymer compound, a composition obtained by mixing a polymer compound not directly related to the emission characteristics of the phosphorescent polymer compound And can also be used as a light-emitting compound. As an example, polymethyl methacrylate (PMMA) or polycarbonate can be mixed in order to impart flexibility to the resulting film.

The thickness of the light emitting layer is preferably 1 nm to 1 μm, more preferably 5 nm to 300 nm, and even more preferably 10 nm to 100 nm.
In the organic electroluminescent element of the present invention, the electroluminescent layer may be the above light emitting layer alone, or may be combined with a hole transfer layer and an electron transport layer.

  Examples of the hole transport compound for forming the hole transport layer include N, N′-dimethyl-N, N ′-(3-methylphenyl) -1,1′-biphenyl-4,4′diamine (TPD), 4,4. '-Bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD), 4,4', 4 ″ -tris (3-methylphenylphenylamino) triphenylamine (m-MTDATA) Examples thereof include known low molecular weight hole transport compounds such as triphenylamine derivatives and polyvinylcarbazole.

  High molecular hole transport compounds can also be used, which are polymerized by introducing a polymerizable functional group into a triphenylamine-based low molecular compound, for example, disclosed in JP-A-8-157575. Examples thereof include polymer compounds having a triphenylamine skeleton, and polymer compounds such as polyparaphenylene vinylene and polydialkylfluorene. These hole transport compounds can be used alone, but may be mixed or laminated with different hole transport compounds. The thickness of the hole transport layer is preferably 1 nm to 5 μm, more preferably 5 nm to 1 μm, and even more preferably 10 nm to 500 nm.

In the organic electroluminescence device of the present invention, examples of the electron transport compound forming the electron transport layer include quinolinol derivative metal complexes such as trisaluminum quinolinol (Alq ₃ ), oxadiazole derivatives, triazole derivatives, imidazole derivatives, and triazine derivatives. Known low molecular weight electron transport compounds can be exemplified. In addition, a high-molecular electron transport compound can also be used, and the above-described low molecular electron transport compound is polymerized by introducing a polymerizable functional group, for example, disclosed in JP-A-10-1665. The poly PBD etc. which can be illustrated can be illustrated. These electron transport compounds can be used alone, but may be mixed or laminated with different electron transport compounds. The thickness of the electron transport layer is preferably 1 nm to 5 μm, more preferably 5 nm to 1 μm, and even more preferably 10 nm to 500 nm.

  The phosphorescent polymer compound used in the light-emitting layer, the hole transport compound used in the hole transport layer, and the electron transport compound used in the electron transport layer are each formed as a single layer, or a polymer compound as a binder. Each layer can also be formed. Examples of the polymer compound used for this include polymethyl methacrylate, polycarbonate, polyester, polysulfone, polyphenylene oxide and the like.

  As described above, in the conventional method, it has been necessary to provide an insulating layer protruding from the level of the electrode surface between the electrodes, but according to the present invention, the insulating layer is not provided or the electrode surface level is provided. The organic electroluminescence layer can be provided on each electrode in a state of being separated from each other only by providing an insulating layer having substantially the same height or less.

The above light-emitting layer (if necessary, hole transport layer and electron transport layer method) is a resistance heating vapor deposition method, an electron beam vapor deposition method, a sputtering method, an ink jet method, a spin coating method, a dip coating method, a printing method, a spray method, It can be formed by a coating method such as a dispenser method or a nozzle coating method. In the case of a low molecular compound, a resistance heating vapor deposition method and an electron beam vapor deposition method are mainly used, and in the case of a high molecular compound, a coating method such as an ink jet method, a spin coat method, a nozzle coat method or the like is mainly used.
As described above, the present invention is particularly effective when pixels are formed mainly by the coating method, but the low molecular vapor deposition method is also very effective in that pixel defects derived from the conventional insulating layer forming method can be avoided. is there.

  In this specification, the ink ejection method mainly refers to an inkjet method in which a coating liquid is ejected in the form of droplets, and a nozzle coating method in which the coating liquid is ejected and applied in the form of a liquid column. These specific methods are described below.

  In the ink jet method, a solution containing a material (in the case of the present invention, an organic electroluminescent material) is ejected as fine droplets onto a substrate from a nozzle hole at the tip of a discharge nozzle attached to a coating apparatus, and a layer containing the material It is a method of forming.

FIG. 4 is a cross-sectional view showing a manufacturing process of the organic electroluminescence device according to the present invention (light emitting layer coating process by ink jet). As shown in this figure, an inkjet coating apparatus head portion (11) smaller than the substrate (S) is used, and the head portion (11) is disposed above the substrate (S). The coating solution (12) is discharged as fine droplets from a nozzle (liquid discharge port) (15) disposed below the head portion (11) with high accuracy and landed on the anode (3). After landing, the droplet spreads in the anode shape according to the volume of the droplet. It is also possible to make the droplets land so as to cover the entire anode surface by enlarging the droplets.
Such an ink jet method has been used more often than ever since it can be patterned finely and easily when a polymer material is used as the material.

  In the nozzle coating method, a solution containing a material (in the case of the present invention, an organic electroluminescence material) is continuously ejected from a nozzle hole attached to a coating apparatus and applied onto a substrate, and a layer containing the material layer It is a method of forming.

  The discharge nozzle includes a nozzle body and a tip member having a nozzle hole, and the tip member can be attached and detached freely. For this reason, if a plurality of tip members having nozzle holes with different diameters are prepared in advance, the fluidity of the coating solution changes depending on the concentration of the organic electroluminescent material in the coating solution, or the type and concentration of the solvent, Even when the optimum flow rate of the discharged solution changes depending on the width of the substrate on which the solution is applied, the tip member attached to the nozzle body is removed and the tip member with a nozzle hole with a diameter that matches the application conditions is removed. By simply exchanging, the solution discharged from the nozzle hole does not become droplets or the flow rate becomes higher than necessary, and the coating solution (12) is always continuously supplied from the head portion (11) as shown in FIG. It can apply | coat in a uniform state on a board | substrate (S) and an anode (3), maintaining the state of a typical liquid column.

  In the manufacturing method of the organic electroluminescence device of the present invention, a coating head having one or a plurality of such discharge nozzles (15) is prepared, and coating is performed in a stripe form from the discharge nozzles (15) as shown in FIG. While discharging the liquid, the organic electroluminescence layer is applied on the ITO substrate by moving the coating head in the long axis direction (X-axis direction) with respect to the ITO substrate.

  When the coating head moves to the end in the major axis direction (X-axis direction) of the substrate, the coating head is fed in the minor axis direction (Y-axis direction) with respect to the ITO substrate, and the coating head is moved in the folding direction. By repeating this operation, the organic electroluminescent material is sequentially applied to the ITO substrate on the substrate.

  According to this configuration, for example, the nozzle hole diameter is set to 15 μm when the ITO substrate width is 140 μm as in Reference Example 2 to be described later, so that the nozzle hole diameter is made smaller than the substrate width. In addition, since there is a margin in positioning the substrate, the electroluminescent material is discharged onto the substrate in a good state without the coating liquid protruding from the anode substrate.

Further, the coating device may include an input device and a display device. By inputting application conditions to the input device, an appropriate diameter of the nozzle hole is appropriately determined based on the input information, and the optimum nozzle diameter is displayed on the display device.
In addition, a storage device may be provided, and by storing information on the correspondence relationship between the application condition and the appropriate size of the nozzle hole diameter corresponding to the condition, it is only necessary to input the application condition to the input device. The proper diameter can be easily determined by selecting an appropriate diameter of the nozzle hole that meets the conditions and setting it so as to be displayed on the display device.

  Further, a hole blocking layer may be provided adjacent to the cathode side of the light emitting layer for the purpose of suppressing the passage of holes through the light emitting layer and efficiently recombining with electrons in the light emitting layer. A compound having a deepest occupied orbital (HOMO) level than the light emitting compound can be used for the hole blocking layer, and examples thereof include triazole derivatives, oxadiazole derivatives, phenanthroline derivatives, and aluminum complexes.

  Furthermore, an exciton block layer may be provided adjacent to the cathode side of the light emitting layer for the purpose of preventing excitons (excitons) from being deactivated by the cathode metal. For this exciton block layer, a compound having a larger excitation triplet energy than the light emitting compound can be used, and examples thereof include triazole derivatives, phenanthroline derivatives, and aluminum complexes.

  FIG. 5 shows an example of a schematic cross-sectional view of the organic electroluminescence device in which the organic electroluminescence layer is formed on the anode substrate in this way. An organic electroluminescence device with a conventional insulating layer and having a hole injection layer is shown in FIG. According to the present invention, the organic electroluminescence layer can be patterned without forming an insulating layer. There are mainly three reasons why this patterning is effective in manufacturing an organic electroluminescent device.

  First, by adjusting the water repellency of the substrate surface, the applied organic electroluminescent compound does not spread unnecessarily and does not overlap with the adjacent pattern, and second, a water-soluble hole injection layer is formed. It is a surface treatment that can emit light only by applying a single layer of an organic electroluminescent compound without using it. Third, when the applied polymer compound is dried to form a film, the applied edge portion is thick. It is to take advantage of the property of having a strong tendency to become a film. By utilizing these properties, it is possible to make the organic electroluminescent layer formed on the edge portion of ITO thicker.

[About cathode]
Next, the cathode (5 in FIG. 6) laminated on the organic electroluminescence layer will be described in detail. As the cathode material of the organic electroluminescence device of the present invention, a material having a low work function and being chemically stable is used, and known cathodes such as Al, MgAg alloy, Al and alkali metal alloys such as AlLi and AlCa, etc. The material can be exemplified, but the work function is preferably 2.9 eV or more in consideration of chemical stability. As a film forming method of these cathode materials, a resistance heating vapor deposition method, an electron beam vapor deposition method, a sputtering method, an ion plating method, or the like can be used. The thickness of the cathode is preferably 10 nm to 1 μm, and more preferably 50 to 500 nm.

  In addition, a metal layer having a lower work function than the cathode is inserted between the cathode and the organic layer adjacent to the cathode as a cathode buffer layer in order to lower the electron injection barrier from the cathode to the organic layer and increase the efficiency of electron injection. May be. Low work function metals that can be used for such purposes include alkali metals (Na, K, Rb, Cs), alkaline earth metals (Sr, Ba), and rare earth metals (Pr, Sm, Eu, Yb). Etc. An alloy or a metal compound can also be used as long as it has a work function lower than that of the cathode. As a method for forming these cathode buffer layers, vapor deposition, sputtering, or the like can be used. The thickness of the cathode buffer layer is preferably 0.05 to 50 nm, more preferably 0.1 to 20 nm, and still more preferably 0.5 to 10 nm.

  Furthermore, the cathode buffer layer can also be formed as a mixture of the low work function substance and the electron transport compound. In addition, as an electron transport compound used here, the organic compound used for the above-mentioned electron transport layer can be used. In this case, a co-evaporation method can be used as a film forming method. In addition to the nozzle coating method according to the present invention, various coating methods such as a spin coating method, a dip coating method, and a spray method are used in addition to the nozzle coating method according to the present invention when coating by a solution is possible. May be. In this case, the thickness of the cathode buffer layer is preferably 0.1 to 100 nm, more preferably 0.5 to 50 nm, and even more preferably 1 to 20 nm.

The completed organic electroluminescence device is shown in FIG. 6, and the conventional device is shown in FIG.
Moreover, the structure of the organic electroluminescent element of this invention is not limited to the example of FIG. 5, 1) a light emitting polymer compound layer / electron transport layer, and 2) a hole transport site | part and light emission in order between an anode and a cathode. Luminescent polymer compound layer / electron transport layer composed of sites, 3) hole transport compound, luminescent compound, luminescent polymer compound layer containing electron transport compound, 3) hole transport compound, layer containing luminescent compound, 4 ) A device structure provided with a layer containing a light emitting compound or an electron transport compound can be exemplified. Moreover, although the organic electroluminescent layer shown in FIG. 4 is one layer, you may have two or more light emitting layers. In the present specification, unless otherwise specified, a compound formed by polymerizing all or one or more of an electron transport site, a hole transport site, and a light emitting site, or a hole transport compound, an electron transport compound, and a light emitting compound A compound formed by mixing all or one or more of these is referred to as a light-emitting polymer compound, and a layer is referred to as a light-emitting compound layer.

  The present invention relates to an organic electroluminescence device as described above, and also includes a surface-emitting light source, a device backlight, a device, a lighting device, an interior, and an exterior equipped with the organic electroluminescence device. Includes electronic equipment.

EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further in detail, this invention does not receive any limitation by these description. In the following examples, materials and layers formed from them are abbreviated as follows for the sake of simplicity.
ITO: Indium tin oxide (anode),
ELP: phosphorescent polymer (poly ((di [4- (3,5-dimethylbiphenyl)]-2,6-dimethyl-4-styrylphenylborane-co-N, N, N′-tris (3- Methylphenyl) -N ′-(4-vinylphenyl) -1,1 ′-(3,3′-dimethyl) biphenyl-4,4′diamine-co- (2- (4-vinylphenyl) pyridine) bis ( 2-Phenylpyridine) iridium (III))).

Reference example 1:
As shown in FIG. 3, the transparent electrode (3) with ITO (indium tin oxide) was patterned on the substrate (S) in a stripe shape. Hereinafter, this substrate is referred to as an anode substrate. The ITO of the anode substrate has a size of 30 μm and a height of 1300 mm, and these pixels are continuously arranged at a pitch of 80 μm.

[Substrate surface treatment]
First, liquid cleaning of the anode substrate was performed. That is, ultrasonic cleaning was performed with a commercially available detergent, and running water cleaning was performed with ultrapure water to produce an anode substrate (A). The contact angle of the anode substrate (A) with respect to water was 10 °.
After the liquid cleaning, the dried anode substrate (A) was mounted in a plasma generation apparatus, and the pressure in the apparatus was set to 1 Pa, the input power was set to 150 W, and the ITO substrate was irradiated with oxygen plasma for 30 seconds.
Next, the type of gas to be introduced was switched from oxygen to CHF ₃ gas, the flow rate was controlled, and the pressure was set to 7 Pa. In PE mode, the input power was 300 W and the substrate was processed for 10 seconds. The treated anode substrate showed water repellency and the contact angle with water was 80 °. The anode substrate having water repellency prepared in this manner was used as an anode substrate (B).

The following solutions (1) to (3) were respectively dropped on the anode substrates (A) and (B) by the ink jet method, and the wet and spread states of the solution around the ITO were observed.
(1) Vitron: A solution obtained by diluting Vitron (poly (3,4-ethylenedioxythiophene) / polystyrenesulfonic acid (manufactured by Bayer)), which is a hole injection compound, 1: 1 with isopropyl alcohol.
(2) ELP-H: A solution obtained by dissolving 60 mg of ELP as an application solution for forming a luminescent compound layer in 1940 mg of anisole (made by Wako Pure Chemical Industries, Ltd., special grade) and filtering through a filter having a pore size of 0.2 μm.
(3) ELP-L: A solution obtained by dissolving 30 mg of ELP as an application solution for forming a light-emitting compound layer in 1970 mg of anisole (made by Wako Pure Chemical Industries, Ltd., special grade) and filtering through a filter having a pore size of 0.2 μm.

  After the dropwise addition of each solution, the solvent was removed in vacuum (1 torr) at room temperature for 30 minutes. After drying, the shape of the formed film was observed with a PL microscope. When the distance between the ITO electrodes indicated by (13) in FIG. 4 is set to 1, the spreading distance of the film is compared with the case where the solutions (1) to (3) are used, and the results are shown in Table 1. .

As shown in Table 1, in the hydrophilic anode substrate (A), all of the above three types of solutions (1) to (3) were spread and contacted with the skirt portion of the solution applied to the adjacent ITO anode. . In particular, the hydrophilic Vitron of (1) spreads to the surface of the adjacent ITO anode, and when ELP was applied, the tendency was particularly remarkable in the ELP-L having a low concentration (2).
On the other hand, in the anode substrate (B) subjected to the water repellent treatment, the hydrophilic vitron of (1) stayed in a spherical shape on the ITO surface and did not spread out. In the case where ELP was applied, the lengths of the skirts of both films (2) and (3) were within the pitch interval, and did not come into contact with the skirt of the solution applied to the adjacent ITO.

Example 1 and Comparative Example 1:
FIG. 7 shows an insulating layer (14) formed by etching a polyimide layer by photolithography on an anode substrate (S) patterned with ITO (3). The opening of the insulating layer is 30 μm, and these pixels are continuously arranged at a pitch of 80 μm. The substrate was washed with liquid, dried, mounted in a plasma generation apparatus, and the pressure in the apparatus was set to 1 Pa, the input power was set to 50 W, and the ITO substrate was irradiated with oxygen plasma for 5 seconds.

Next, the type of gas to be introduced was switched from oxygen to CHF ₃ gas, the flow rate was controlled, and the pressure was set to 7 Pa. In PE mode, the input power was 300 W and the substrate was processed for 10 seconds.
When compared with a separately prepared substrate formed with polyimide without water repellent treatment, it was confirmed that the polyimide layer constituting the treated insulating layer showed a contact angle of 95 ° with respect to water.
The anode substrate having the water-repellent insulating layer thus produced was designated as an anode substrate (C).

  The solution (1) shown in Reference Example 1 was applied to the anode substrate (C) by an ink jet method, dried at room temperature for 20 minutes, and further dried at 150 ° C. for 1 hour in non-atmosphere. Thereafter, the solution (3) shown in Reference Example 1 was applied by an ink jet method and laminated on the layer (1). The anode substrate (C) thus formed with the light emitting layer was placed in a vapor deposition apparatus, and calcium was vapor-deposited to a thickness of 10 nm at a vapor deposition rate of 0.01 nm / s. Subsequently, aluminum was deposited as a cathode to a thickness of 150 nm by sputtering, and finally sealed with an epoxy resin.

In the same manner, the anode (B) produced in Reference Example 1 was coated with the solution (3) shown in Reference Example 1 to form a light emitting layer, and then a cathode was formed. Thus, the device produced with each anode substrate (C) and (B) was made into the organic electroluminescent apparatus (C) and the organic electroluminescent apparatus (B).
The ratio of pixels in which defects such as short circuits are observed to 100 pixels manufactured in parallel with each organic electroluminescent device is about 32 in the organic electroluminescent device (C), and the organic electroluminescent device (B ) Was about seven.

The result of having measured the emission spectrum by making the pixel of organic electroluminescent apparatus (C) and (B) emit light is shown in FIG. As can be seen from the results, both showed good green light emission.
FIG. 15 shows a graph comparing pixel lighting durability times of the organic electroluminescence devices (C) and (B). These results show that the organic electroluminescence device (B) prepared without using the insulating layer and the hole injection layer is more organic than the organic electroluminescence device (C) prepared using the insulating layer and the hole injection layer. This shows that yield and durability are expected to improve.

Reference example 2:
As shown in FIG. 3, the transparent electrode (3) with ITO (indium tin oxide) was patterned on the substrate (S) in a stripe shape. Hereinafter, this substrate is referred to as an anode substrate (2). The size of the ITO of the anode substrate (2) is 140 μm in width and 1300 mm in height, and these pixels are continuously arranged at a pitch of 130 μm.

[Substrate surface treatment]
First, liquid cleaning of the anode substrate was performed. That is, ultrasonic cleaning was performed with a commercially available detergent, and running water cleaning was performed with ultrapure water to produce an anode substrate (2A). The contact angle of the anode substrate (2A) with respect to water was 10 °. After the liquid cleaning, the dried anode substrate (2A) was mounted in a plasma generating apparatus, and the pressure in the apparatus was 1 Pa, the input power was 150 W, and the ITO substrate was irradiated with oxygen plasma for 30 seconds.

Next, the type of gas to be introduced was switched from oxygen to CHF ₃ gas, the flow rate was controlled, and the pressure was set to 7 Pa. The substrate was processed for 10 seconds with an input power of 300 W in PE mode. The treated anode substrate showed water repellency and the contact angle with water was 80 °. The anode substrate having water repellency prepared in this manner was used as an anode substrate (2B).

  As a coating solution for forming the luminescent compound layer on the anode substrates (2A) and (2B), the solution (3) prepared in Reference Example 1, that is, 60 mg of ELP was changed to 1940 mg of anisole (made by Wako Pure Chemical Industries, Ltd., special grade). A solution was prepared by dissolution and filtration through a filter having a pore size of 0.2 μm. This solution was applied onto the anode substrates (2A) and (2B) by a nozzle coating method. The conditions of the nozzle coating method were a nozzle diameter of 15 μm, a flow rate of 180 ul / min, a scanning speed of 3 m / sec, and only one anode substrate (2A) was coated with ITO. After coating, the film was heated at 100 ° C. for 15 minutes and dried, and the film thickness was measured. The film thickness was 800 mm.

  FIGS. 16 and 17 show the results of irradiating the substrate (2A) and (2B) after application of the light emitting layer solution with light of 340 nm to emit ELP and observing the surface state with a PL microscope. In the anode substrate (2A) (FIG. 16), the ELP is clearly unevenly spread and straddles adjacent ITO, whereas in the anode substrate (2B) (FIG. 17), the ELP film is in a good linear state. Was formed.

  Moreover, the result of having measured the surface shape of the anode board | substrate (2B) after ELP application | coating with the surface level | step difference meter (made by TENCOR) from the direction orthogonal to the ITO stripe was shown in FIG. According to this, the ELP layers do not overlap between adjacent ITO, and are clearly disconnected, and the film thickness is increased in the vicinity of the edge of the ITO, and an effect of suppressing a short circuit at the edge can be expected.

Example 2 and Comparative Example 2:
In FIG. 19, the polyimide layer was etched by photolithography to form an insulating layer (14) so as to be parallel to both sides of ITO (3) patterned in a stripe pattern on the anode substrate (S).
The opening of the insulating layer is 80 μm, and these pixels are continuously arranged at a pitch of 80 μm. The substrate was washed with liquid, dried and mounted in a plasma generating apparatus, and the pressure in the apparatus was set to 1 Pa, the input power was set to 50 W, and the ITO substrate was irradiated with oxygen plasma for 5 seconds.

Next, the type of gas to be introduced was switched from oxygen to CHF ₃ gas, the flow rate was controlled, and the pressure was set to 7 Pa. The substrate was processed for 10 seconds with an input power of 300 W in PE mode.
When compared with a separately prepared substrate formed with polyimide without water repellent treatment, it was confirmed that the polyimide layer constituting the treated insulating layer showed a contact angle of 95 ° with respect to water.
The anode substrate having the water-repellent insulating layer thus produced was designated as an anode substrate (2C). The solution (2) prepared in Reference Example 1 was applied to the anode substrate (2C) by a nozzle coating method. The anode substrate thus formed with the light emitting layer is placed in a vapor deposition apparatus, and calcium is vapor-deposited to a thickness of 10 nm at a vapor deposition rate of 0.01 nm / s, followed by sputtering with aluminum as a cathode to a thickness of 150 nm. A film was formed and finally sealed with an epoxy resin.

By the same method, the solution (2) prepared in Reference Example 1 was applied to the anode substrate (2B) prepared in Reference Example 2 to form a light emitting layer, and then a cathode was formed.
The devices thus prepared using the anode substrates (2C) and (2B) were designated as an organic electroluminescence device (2C) and an organic electroluminescence device (2B), respectively. The ratio of pixels in which defects such as short circuits are observed to 100 pixels manufactured in parallel with each organic electroluminescence device is about 20 in the organic electroluminescence device (2C) and about 3 in (2B). It was a piece. FIG. 20 is a light emission photograph of the organic electroluminescence device (2C), and it can be seen that the width of the light emitting portion is not uniform.

Example 3: Application of SiO ₂ by sputtering The ITO anode substrate was set in a DC sputtering apparatus (manufactured by Anelva), and the substrate surface was sputtered for 1 minute. The conditions at this time were SiO ₂ as the target, the input power was 0.3 kW, nitrogen was used as the gas, and the pressure during sputtering was 1 Pa. This anode substrate having water repellency is referred to as an anode substrate (3). The contact angle of water on the anode surface (3) after the sputtering treatment was 70 degrees.
After applying ELP by the nozzle coating method in the same manner as in Example 2, a cathode was formed, and an organic electroluminescence device (3) was produced.

  According to the method of the present invention, an organic electroluminescent light emitting compound can be applied without forming an insulating layer on the anode substrate surface, which was essential in the conventional method, and a stable and high performance organic electroluminescent device is manufactured. I can do it.

It is sectional drawing of the conventional organic electroluminescent apparatus which has a 1st insulating layer and a 2nd insulating layer. (A)-(d) shows the manufacturing method (process) of the organic electroluminescent apparatus of FIG. It is a schematic sectional drawing of the board | substrate used for the organic electroluminescent apparatus which concerns on this invention. It is sectional drawing which shows the manufacturing process (application | coating of the light emitting layer by the inkjet method) of the organic electroluminescent apparatus which concerns on this invention. It is a schematic sectional drawing of a part of the board | substrate obtained by the method of this invention which apply | coats an organic electroluminescent compound using a water repellent treatment board | substrate. It is a schematic sectional drawing of the part of the organic electroluminescent apparatus manufactured by the method of this invention. It is a schematic sectional drawing of the board | substrate used for the organic electroluminescent apparatus by the conventional method. It is a schematic sectional drawing of a part of board | substrate obtained by apply | coating an organic electroluminescent compound to a board | substrate by the conventional method (comparative example) using a water-repellent treatment board | substrate. It is a schematic sectional drawing showing the structure of the insulating layer of this invention. It is sectional drawing which shows the manufacturing process (application | coating of the light emitting layer by a nozzle coat method) of the organic electroluminescent apparatus which concerns on this invention. It is the schematic of the coating method at the time of apply | coating an organic electroluminescent compound by the nozzle coat method. It is a schematic sectional drawing which shows the cross section of a part of board | substrate with which the organic electroluminescent compound was apply | coated by the conventional method. It is a schematic sectional drawing of the part of the organic electroluminescent apparatus manufactured by the conventional method. The emission spectrum obtained from the organic electroluminescent apparatus (Example apparatus B and Comparative example apparatus C) produced with this invention and the conventional manufacturing method is shown. It is a graph which shows durability of the organic electroluminescent element (Example apparatus B and Comparative example apparatus C) produced with this invention and the conventional manufacturing method. The PL microscope picture showing the surface state of the anode substrate (2A) created by this reference example 2. FIG. The PL microscope picture showing the surface state of the anode substrate (2B) created by this reference example 2. FIG. The result of having measured the surface shape of the anode substrate (2B) created by this reference example 2 with the surface level | step difference meter. It is a schematic sectional drawing of the anode substrate (2C) created in the present Example 2. The light emission photograph of the organic electroluminescent apparatus (2C) created in this Comparative Example 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st insulating layer 2 2nd insulating layer 3 Anode 4 Light emitting layer 5 Cathode 6 The area | region where the light emitting layer is thin 7 Etching residue of opening part 8 Etching residue of surface relief part 9 Hole injection layer 10a Red organic electroluminescent compound 10b Green organic electroluminescent compound 10c Blue organic electroluminescent compound 11 Inkjet coating device head part 12 Coating solution 13 ITO spacing 14 Insulating layer 15 Discharge nozzle B Organic electroluminescent device C according to the present invention Organic electroluminescent device S according to the conventional method Substrate

Claims (26)

  In a method for manufacturing an organic electroluminescent device in which an organic electroluminescent layer is formed on each electrode by applying a composition containing an organic electroluminescent compound on a plurality of electrodes, water repellent treatment is performed between the electrodes and / or on the surface of the electrodes. The manufacturing method of the organic electroluminescent apparatus characterized by using the board | substrate which gave this, and apply | coating the said composition.   The method for producing an organic electroluminescent device according to claim 1, wherein the water repellent treatment includes formation of a water repellent thin film.   The method for producing an organic electroluminescent device according to claim 2, wherein the water-repellent thin film has a thickness of 0.2 to 30 nm.   The organic electroluminescence according to claim 2, wherein an insulating layer having a thickness of 0 to 3000 nm from the substrate surface and an angle of 0 to 80 degrees viewed from the upper surface of the electrode is provided around the plurality of electrodes formed with the water repellent layer. Device manufacturing method.   The organic electroluminescence according to claim 4, wherein an insulating layer having a thickness of 0 to 500 nm from the substrate surface and an angle of 0 to 30 degrees viewed from the upper surface of the electrode is provided around the plurality of electrodes formed with the water repellent layer. Device manufacturing method.   The method for producing an organic electroluminescent device according to claim 1, wherein the organic electroluminescent layer is a layer containing a polymer organic electroluminescent compound.   The method for producing an organic electroluminescence device according to claim 2, wherein the method for forming the water-repellent thin film is a treatment for forming a fluoride film on the surface of the substrate.   The method for producing an organic electroluminescence device according to claim 7, wherein the fluoride film is formed by plasma treatment using a fluorocarbon compound as a reaction gas.   The method for producing an organic electroluminescence device according to claim 2, wherein the surface roughness of the water-repellent thin film is 1 nm or less in terms of Ra value.   The method for producing an organic electroluminescence device according to claim 2, wherein the surface protrusion height of the water-repellent thin film is 10 nm or less.   The method for producing an organic electroluminescence device according to claim 2, wherein the water-repellent thin film is formed as an organic thin film by a radio frequency (RF) plasma treatment method of a gaseous organic compound.   3. The method of manufacturing an organic electroluminescence device according to claim 2, wherein the anode (surface) is subjected to high-frequency plasma treatment, and then a thin film is formed and then optimized to form a water-repellent thin film.   3. The method according to claim 2, wherein after the anode (surface) is subjected to a high frequency plasma treatment, a thin film is formed by a radio frequency (RF) plasma treatment method of a gaseous compound, and then optimized to form a water-repellent thin film. The manufacturing method of the organic electroluminescent apparatus of description. The method for producing an organic electroluminescent device according to claim 2, wherein the method of forming the water-repellent thin film is a method of forming a SiO ₂ thin film by treating the substrate surface by a sputtering method.   The method for manufacturing an organic light-emitting element according to claim 12, wherein the optimization process is a cleaning process using a solvent.   The organic light-emitting device according to claim 12 or 13, wherein high-frequency plasma treatment is performed in a gas containing one or more selected from oxygen, argon, and fluorocarbon in order to adjust the surface roughness of the anode and the height of the protrusions. Production method.   The method for producing an organic electroluminescence device according to claim 2, wherein the contact angle of water with the water-repellent thin film is 30 ° or more.   The manufacturing method of the organic electroluminescent apparatus of Claim 1 or 2 which apply | coats the composition containing an organic electroluminescent compound on a some electrode by a letterpress printing, an intaglio printing, a stencil printing, or a plateless printing method.   The manufacturing method of the organic electroluminescent apparatus of Claim 18 which apply | coats the composition containing an organic electroluminescent compound by the plateless printing method by an ink jet.   The manufacturing method of the organic electroluminescent apparatus of Claim 18 which apply | coats the composition containing an organic electroluminescent compound by the nozzle coat method.   The method for producing an organic electroluminescent device according to claim 1, wherein the organic electroluminescent compound is a phosphorescent polymer compound.   The method for producing an organic electroluminescent device according to claim 1, wherein the organic electroluminescent compound is a fluorescent light-emitting polymer compound or a non-conjugated phosphorescent polymer.   An organic electroluminescence device manufactured by the manufacturing method according to claim 1.   The substrate for organic electroluminescent devices manufactured by the method included in the manufacturing method of any one of Claims 1 thru | or 22.   An electronic device comprising the organic electroluminescence device according to claim 23. The electronic device according to claim 25, wherein the electronic device is a surface-emitting light source, a device backlight, a device, a lighting device, an interior, or an exterior.

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